This application is based on and incorporates herein by reference Japanese Patent Application No. 2001-31447 filed Feb. 7, 2001.
The present invention relates to a cooling mechanism for cooling an engine electronic control module (ECM), which is less affected by heat of a vehicle engine. Here, the engine electronic control module, mounted in a vehicle, performs an electronic control such as a fuel injection control.
A conventional engine electronic control module, mounted in a vehicle, is disposed in a passenger compartment to be protected from heat of a vehicle engine. Since many of sensors for the engine electronic control module are disposed in an engine compartment, wiring length becomes longer between the engine electronic control module and the sensors, thereby increasing wiring work, wiring cost and a wiring space. Further, electromagnetic noise is generated in the wiring.
It is therefore proposed in JP-A-H6-137146 to cool a computer of an engine electronic control module mounted in a vehicle in the following manner. That is, the computer contained in a case is disposed in an intake pipe, and only wiring harnesses are taken out from the intake pipe, so that a temperature of the computer is restricted from being increased using air flowing in the intake pipe. Otherwise, the computer contained in the case is disposed on the intake pipe so that a radiation body integrated with the case protrudes inside the intake pipe, so that the temperature of the computer is decreased through the radiation body using air flowing in the intake pipe.
However, in this cooling manner, eddies of air cannot be prevented from being irregularly generated at an upstream side of an air flow meter. Therefore, since an air-flow amount signal from the air flow meter becomes unstable, engine output characteristics become unstable. Further, since air flows toward a non-restricted part in the intake pipe, a sufficient cooling effect cannot be obtained.
Therefore, the present invention has an object to provide a cooling mechanism which can effectively cool an engine electronic control module so that the engine electronic control module can stably obtain an air-flow amount signal from an air flow meter by restricting eddies of air from being irregularly generated at an upstream side of the air flow meter.
In a cooling mechanism for an engine electronic control module according to one aspect of the present invention, a base plate of an engine electronic control module is attached to the intake pipe from which air is sucked for an engine. The base plate includes air rectifier fins for cooling the engine electronic control module, for concentrating suction-air streams at a position on the base plate while rectifying the suction-air streams, and for transferring the suction air to an suction-air introduction port of an air flow meter. Therefore, eddies can be prevented from being irregularly generated at an upstream side of the air flow meter, so that an air-flow amount signal can be stably obtained from the air flow meter. Additionally, the engine electronic control module can be effectively cooled.
According to another aspect of the present invention, an introduction plate or an air-stream changing mechanism is provided in the intake pipe at an upstream side of the base plate singly or in addition to the air rectifier fins.